Messages in this thread | | | Date | Wed, 31 Aug 2022 10:43:47 +0200 | From | Johan Hovold <> | Subject | Re: [PATCH 1/2] USB: serial: ch341: fix lost character on LCR updates |
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On Wed, Aug 31, 2022 at 10:36:18AM +0200, Jiri Slaby wrote: > On 31. 08. 22, 10:15, Johan Hovold wrote: > > Disable LCR updates for pre-0x30 devices which use a different (unknown) > > protocol for line control and where the current register write causes > > the next received character to be lost. > > > > Note that updating LCR using the INIT command has no effect on these > > devices either. > > > > Reported-by: Jonathan Woithe <jwoithe@just42.net> > > Link: https://lore.kernel.org/r/Ys1iPTfiZRWj2gXs@marvin.atrad.com.au > > Fixes: 4e46c410e050 ("USB: serial: ch341: reinitialize chip on reconfiguration") > > Fixes: 55fa15b5987d ("USB: serial: ch341: fix baud rate and line-control handling") > > Cc: stable@vger.kernel.org # 4.10 > > Signed-off-by: Johan Hovold <johan@kernel.org> > > --- > > drivers/usb/serial/ch341.c | 10 +++++++++- > > 1 file changed, 9 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c > > index 2798fca71261..2bcce172355b 100644 > > --- a/drivers/usb/serial/ch341.c > > +++ b/drivers/usb/serial/ch341.c > > @@ -97,7 +97,10 @@ struct ch341_private { > > u8 mcr; > > u8 msr; > > u8 lcr; > > + > > unsigned long quirks; > > + u8 version; > > Could you move version above quirks? That would not create another > 7-byte padding in here. Actually it would not make ch341_private larger > on 64bit at all, if I am looking correctly.
No, I added it after quirks on purpose as it isn't protected by the spinlock and doesn't change during runtime like the shadow registers.
And I really don't care about saving 8 bytes on 64-bit. :)
Johan
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